package com.atguigu.gmall.realtime.util;

import java.util.concurrent.LinkedBlockingDeque;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

/**
 * @author Felix
 * @date 2022/11/29
 * 获取线程池对象的工具类
 *  双重校验锁解决单例设计模式懒汉式线程安全问题
 */
public class ThreadPoolUtil {

    private static volatile ThreadPoolExecutor poolExecutor;

    private ThreadPoolUtil() {}

    public static ThreadPoolExecutor getInstance(){
        if(poolExecutor == null){
            synchronized(ThreadPoolUtil.class){
                if(poolExecutor == null){
                    System.out.println("~~创建线程池对象~~");
                    poolExecutor
                        = new ThreadPoolExecutor(4,20,300, TimeUnit.SECONDS,new LinkedBlockingDeque<Runnable>(Integer.MAX_VALUE));
                }
            }
        }
        return poolExecutor;
    }
}
